Current microprocessor based engine control systems communicate with a number of system devices. The engine control systems transfer input and output (I/O) signals between system devices using both serial and parallel signal pathways.
Present engine control systems have non-selectable signal pathways for the I/O signals that dedicate I/O signals and pin usage. Therefore, the systems have a very inflexible design in terms of I/O usage. There is a need for increased versatility of I/O signal and pin usage that allows multiplexing of alternative I/O signal pathways to device pins.